Method of producing color separation images



June 1, 1943. B; GASPAR 2,320,358

METHOD OF PRODUCING COLOR SEPfr-LTION IMAGES Filed Jan. 24, 1941 hmm gr e en .sens/Wye.

ewa/whos.

sap/Boff Bela' Gaspar Paten-'ted June 1,1943

'UNITED gs'ltli'rlzs PATENT ori-lcs Ma'rnon oF PitoDUoING coLon SEPA-- RA'rioN IMAGES Bla Gaspar, Hollywood, Calif., asslgl'lor to` Chromogen, Incorporated, a corporation of Nevada Application January 24, 1941,'seria1 No. 375,849

My invention pertains to the use of multilayer materials for the making of photographs and to the production of color separations from such photographs. Heretofore, it has been the common practice to develop, and tone or otherwise transform into dye images'all of the components or part-images in -such a multilayer material, and then use them for the making of copies or color separations. In other Words, alljof these prior processes involve development of all of the partimages prior to the copying step.

.12 claims. (C1. 95-2) bellen, Leipzig, 1931, vol. 2, pg. 232) per square meter in gelatin. The back element of the bipack includes a support! which carries a'redsensitive silver .bromide emulsion layer C sensitized withpinacyanol.

. emulsion of the reversal" type which has similar v properties as to gradation and contrast as those It is an object of my invention to providea .I

new and improved method for the preparationv of color separations wherein preferably only one v of the superposed and integrally united layers of a multilayer material, each containing a-latent image of a color separation, is separately develcped and printed without affecting the latent images in the other layers.

Another and still further object of my invention is to provide such a process vin which the integrally attached layer containing a rlatent image is rendered optically homogeneous so that found in ordinary reversible cinema llms.'A On top of this layer C is coated a green-sensitive emulsion layer B which has been sensitized with thiopseudocyanine.

'I'he bipack material shown in Fig. 1 isexposedv in a. camera, separated, and the fIontJeIement the developed image maybe printed therethrough without interference.

'.lov these and other ends the invention resides in and in combinations of elements all as will be more fully described hereinafter, the novel features being pointed Vout in the claims appended ereto. A

- In the accompanying drawing, Fig. 1` is a sectional view of a bipack illm having three lightsensitive layers and a iilterlayer, oneof the layers being a reversal emulsion. Fig. 2 shows a sectional view of a multilayer material having three light-sensitive layers and a filter layer on a single support, two of the emulsion layersbecertain improvements in processing methods :zu in such a way as to develop only vthe surfacel ing reversal emulsions. Figure 3 likewise" shows a multilayer material having three light-sensitive layers and two filter layers, all of the lightsensitive layers being reversal emulsions.

Example one t In Figure 1 ofthe accompanying drawingyf have shown a. multilayer photographic material in the form ofa bipack -which may be used asa)` taking material and later processed in accordance with my invention. 'I'he material is adapted for exposure through the support l. This bipack includes a transparent blue-sensitive emulsion layer A on the front support I. Over this bluesensitive emulsion layer is coated a yellow illter layer A' containing onev gram of calcium salt of the dye xylenwalkgelb G (Schultz ll'arbstoil'eta including the layer -A is developed normally, whereupon the image may be printed onto a positive film to form a blue separation mastery positive. The back element of the bipack isdeveloped in a rapid as the following;

` fr-- '15o Water Methyl alcohol cc-- '148 Metol A L .;ecc 14 Hydroquinone -cc y14 Sodium sulphite anhydr l -grams 52.5 sodium hydroxide v -do 3.a` Potassium bromide s do 8 8 Water to er' 1000 This rapid development is caused to take place layer. B with the aforementioned developer. 'Ihe l time .of development has been found to take al1-` Layer C is a reversible i 4silver bromide emulsion, and ls preferably an developer, such Vfor example f proximately one minute. However, the exact time' of development-for any particular material should be established by a preliminary test. When the surface layer-B has been developed, development is stopped with a 1% .solution Voi' aceticaid and theillm'is washed and dried; The illm'is then printed with infra-red light having 'a wave length of v4over '100 mi onto a positive film which has been sensitized to infra-red with cryptocyanlne or benzthiotricarbocyanine. One thus obtains a. green separation master positive from the developed image inlayer B without disturbing the latent image in layer C.

After the surface layer B has been printed, the underlying layerC is developed and the developed silver is bleached in both layers B and C. This may be done by transforming the silver images into a comparatively insensitive silver Y bromide by treatment with a' 10% solution of cupric bromide for about 10 minutes. As a result of this treatment layer B is rendered optically homogeneous, i. e;,'it contains the original longer red-sensitive and `layer B is only sensitive to green with a possible inherent sensitivity to blue. Due to the fact that layer B is optically homogeneous it presents a. minimum of interference to the passage of the printing light.

It will be understood of course that the print obtained by printing layer C will be a negative, whereas the prints obtained from layers A and B will be positives. This fact must be taken into consideration during the subsequent utilization of the prints.

-A simple modification of the material shown in Fig. 1 is to interpose a filter layer between the layers B and C and to color this lter layer with a yellow dye which will absorb blue and ultra-violet. It is then possible to expose layer i C through the support to a strong blue or ultra violet light in order to accomplish the reversal,

and the iilter layer prevents the exposure from affecting layer B.

i. Example two In Fig.`2 I have shown a multilayer material l in which three light sensitive silver halide layers are coated on a single Support 2. On this sup` port is coated a red sensitive silver halide emul- .sion C of the reversal type, and superposed with respect to'this is a green sensitive emulsion B also of the reversal type. 0n top of this emulsion B is coated a illter layer A' containing a yellow dyestul'i, as in Fig. 1, followed by an ordinary blue sensitive emulsion A.

After this material has been exposed in a camera in the ordinary manner, the top layer A is developed in a rapid developer as described in Example one, and the developer is controlledin such a way as to interrupt the development after the layer -A has been completely developed: The image in layer A is then printed with infra red light onto an infra red vsensitive film as also described in Example one. Following the printing of the image in layer A, theremaining layers B and C are developed in an ordinary A 'developer and the nlm is treated withA a solu- 1 tion of 55% acetic acid which actsas a stop bath.'and washed. It is then treated with a bath containing 245%v of potassiumferricyanide and 0.5-2% potassium iodide to transform the developed silver images in all of the layers into silver iodide.' The developed silver images can also be transformed A-into-a comparatively insensitive silver bromide by treating them with a 10% solution of cupi-ic v.bromide as described in Example one. Either treatment renders all of the layers optically homogeneous.. `The nim is now washed and dried and exposed with intenseA red light and again developed toform a reversal image in layer C. This image may now be printed with infra red light' or with red light, since none ofthe layers is sensitive to light outside the blue and green spectral ranges.

Here again the fact that layers A and B have been rendered optically homogeneous at the time the reversed image in .l .iacilitatesthe passage of the layer C 1S Printed,

a minimum of interference. The layerscontain the original silver bromide which has not been fixed out, and also the original images recorded therein. However, theoriginal images are now in the form of silver iodide or silver bromide which has substantiallythe same optical properties as the original silver bromide. This condition is important, since if the developed silver images in all of the layers had been dissolved prior to reexposure and printing of layer C. then atthe time of printing the image in layer C it would have been falsiiled by the minor but material opacity of the residualsilver salt images in layers A and B.

After the reversed image in layer C has been printed onto a separate material sensitive to the light utilized for printing, the film is again treated with either of the above mentioned bleaching baths to transform the reversed silver image in layer C back into either silver iodide or comparatively insensitive silver bromide, thus making layer C optically homogeneous again. The iilm is then again exposed to intense green light to reverse the image in layer B. This reversed image in layer B can be printed with infrared light, red or even green light, or the `silver saltcan be fixed out of the whole illm and the image in layer B can thenv be printed with White light.

`. After the bleaching steps in the foregoing procedure, the illm can be treated in a 5% solution of sodium sulphite to which some sodium hydroxide or some ammonia may be added, in order to increase its sensitivity. Alternatively. one may use a bath containing 0.5-10 cc; of concentrated ammonia per liter of water.

In this example, as in Example one, due allowance must be made in utilizing the prints made from the images in@x layers A, B and C, for the fact that the imagesobtained from layers B and C are negatives while the image obtained from layer A is a positive.-

Emample three The material shown innig. 3 has three iight sensitive silver halide layers superposed on a support. The layer C is ared sensitive layer.

the layer B is a green sensitive layer, and the layer A is an ordinary blue sensitive layer. Interposed between layers A and B is a yellow lter layer A', and if desired a red filter layer B' is interposed between layers B and C. All of theselight sensitive emulsions are reversal emulsions. They may be sensitized as disclosed in Example one, and the illter layer A' may be dyed with the yellow dye suggestedin Example one while the iilter layer B may be -dyed with any suitable red dyestui! such as l gram of Parared per square meter as described in my U. S. Patent 2,172,307.

After exposure in a camera inthe ordinary way, the ijllm is developed-with an ordinary developer to form a silver image in each of the three layers. is treated with a V20/tsolution of acetic acid which acts as a. stop bath, and washed but not ilxed. The developed silver images in all three layers are then transformed into silver salt images by treatment in either of the following solutions:

(1) A solution of 25%of potassium ferricyanide and 0.5-2% potassium iodide.

(2) A 10% solution of cupric'bnomide.

' Treatment in solution (l) results in the transprinting light with 75 formation oi? the developed silver images into Following development, theillrn the .transformation of the developed silver images into a comparatively insensitive silver bromide after a treatment of about ten minutes. Treatment of the film with either of these solutions results in the production of optically homogeneous layers as brought out in Example two.

Following the foregoing treatment, the film is washed and dried. It is then exposed with an intense red light which aiects the undeveloped lowing this reexposure the illm is developed to form a reversal of the red separation image in layer C and the 111m is Washed, dried and printed with infra red or red light onto an infra red or red sensitive illm `to produce a negative of the red separation image. Following this printing step the iilm is again treated with either solution (l)` or (2), whereby the positive image in cally homogeneous. .l After being again washed and dried, the film is exposed to a strong green light which affects the undeveloped silver bromide in layer B. After development a reversed image is formed in layer B and this image can be' reversed image in layer B and to render` this layer optically homogeneous. The film may now be exposed to blue light and developed to produce a reversed image in laye;` A. This image can then be printed as above described to produce a negative of the blue separation image. It is also possible to ilx the iilm following development of the last reversed image, in which case the reversed image in layer A could be printed with ordinary white light.

It will be understood, of course, that the order of reexposure and printing can be varied. For example, the image in layer B might be reversed and printed first instead of the image in layer C. If layer B is reversed and printed first, it; might be printed with red light onto a red sensitive layer even though layer C still contains red sensitive silver bromide. The printing oflayer B with red light would, of course, cause a certain proportion of the red sensitive silver bromide in layer C tobe exposed. However, this does not intertere with the succeeding treatment of layerC 3 esses are eliminated. Also, the overlapping of individual part images is totally eliminated, and

this is a result that can normallybe obtained only when separation part images are made from multicolor part images of a. multilayermaterial -by the application of cumbersome methods.

I have herein shown and particularly described certain embodiments of my invention and variations of the improved method embraced therein for the purpose of explaining its principle .and

' f application but it will be obvious to those skilled silver bromide in the red sensitive layer C. Follayer C is bleached and layer C is rendered optiin the art that many modications'and other cordingly, it should be definitely understood that when. I refer to reversible emulsions I mean to include any emulsion which can be reversed whether or not it is specially adapted for such treatment.

What I claim and desire to secure by Letters 1. 'I'he method of producing photographic unexposed silver halide in said layers and havsince following the printing of the image in layer B, layer Cis completely exposed to red light. Therefore, the incidental exposure of layer C during the printing of layer B is .merely cumulative with regard to the complete exposure of layer C and the reversed image produced in layer C will be Just the same even though layer C was incidentally exposed during the printing of layer B. In this regard it will be noted that 'the improved process is not limited to printing one of the developed images with light to which none of the other light sensitive layers is responsive. It

v will be understood, of course, that if any one of the layers is printed with light which would be absorbed by lthe filter dye in the intervening illter 1 layers. itis necessary to remove this dye prior to such printing.

The advantages of the present method will .be readily understood from a consideration of the foregoing examples, and it is to be particularly noted that the method excels in its simplicity and in the i'act that intricate toning and dyeing procing substantially :insensitivity to thelight and substantially no reactivity with regard to the developer used in the further processing, selectively exposing the remaining light sensitive silver halide in one of said emulsion layers, and developing and printing the Aresulting reversal image. l

2. The method of producing photographic images from a multilayer photographic material including a plurality of light sensitive silver halide emulsion layers each containing a latent image and at least one of said emulsion layers being of the reversal type which comprises, developing the latent images in said emulsion layers, transforming the developed images into a silver salt having substantially the same optical,

vimages from a multilayer photographic material including a plurality of light sensitive silver` halide emulsion layerseach containing a latent image which comprises, developing the latent images in said emulsion layers, transforming the developed images into a silver salt having substantially the same optical properties as the unexposed silver halide in said layers and having substantially no sensitivity to the light and substantially no reactivity with regard to the developer used in the further processing, selectively exposing the remaining light sensitive silver halide in one of said emulsion layers, developing and printing the resulting reversal image, transforming said reversal image into a silver salt having substantially the sameoptical properties as the remaining silver salt in said one of said emulsion layers and having substantially no sensitivity to the light and substantiallyno reactivityiwith regard to the developer. used in-the further processing, selectively exposing the remaining lightfsensitive silver halide in another cri emulsionl'ayenand developing and printing the 'resulting reversal imagel in said other emulsion'f'f layer.v v 4. The v images 'from a multilayerv photographic' matemethpd of "producing photographic# rial including three light sensitive-silverv halide emulsion layers each containing a latent'fimage; i"

wh'ichr'zornprises,v developing the latent images in said, emulsion layers, transforming` the de-xAV velopedv images into a silver salt having substanv tially the ksame optical properties asvthe unex-f posed 'silver halide in said layers and having j: substantially-no sensitivity to the light and sub- 'f stantially, no reactivity with regardfto the' developer used in the further processing, selectively exposingxthe remaining light 'sensitive'silver halide inone of said layers, developing and printing .the resultingreversal image, trans-.- forming the developedfreversal imageinto asili/er,r

salt having: substantially the samev optical" p`rop'-,l

verties as the remaining silversalt in said one .of said layers and having substantially no-sensitivity to the light and Substantially no reactivity with regardto thedeveloper used inthe further processing, selectively exposing the remi'iiningy light sensitive silvery halide in one of the other emulsion layers, developing and printing the resulting reversal image in the last mentioned layer, transforming the developed image in said last mentioned layer into a silver salt having substantially the same opticalpro'perties as the remaining silver salt in the layer and having substantially no sensitivity to the light and substantiallyv no reactivity with regard to the developer used in the further processing, selectively exposing the remaining light sensitive silver halide in the third emulsion, and developing and printing the resulting reversal image.

5. 'I'he method of producing photographic images from a multilayer photographic material including three light sensitive silver halide emulsion layers each containing a latent image which comprises, developingthelatent images in said emulsion layers, transforming th'eLdevelf oped images into a silver salt having vsubstantially the same optical properties as the unex- `posed silverV halide in said layers and having substantially no sensitivity tothe light and substantially no reactivity with regard to the developer used in the further processing, selectively exposing the remaining light sensitive silver halide in one of said layers, developing and printing. the resulting reversal image, transforming thev developed reversal image into `a silver salt having substantially the same optical propertiesl as the remaining silver salt in said oneof said layers and having substantially no sensitivityto the light and substantially no reactivity with re' ing :the remaining light sensitive silver halide in thethirdemulsion, developing, iixing, and printing the resulting reversal image.

6;-'l."l1ek method of producing photographic imagesr from. a multilayer photographic materialfincluding `a plurality ofjlight sensitive silver n Vhalide*,einul'sion -layers each containing a latent image whichvcomprises, developing the vlatent j images-'in said: emulsion layers, transforming the 10,

developed images into a silver salt having substantially the sameoptical propertiesA as the unexposedsilver. halide lin saidlayers and having substantially [no sensitivity to the light and suby stantially'fno reactivitywith regard to the dp- ,veloper used inzthe further processing. selec- `tivelvexposing.the remaining light sensitive silver;halidezirionepf s aid emulsion layers, and developing` and printing the resulting reversal image ,Witli infra:l VredY light.

'IThe methodv` of. producingV photographic images from a1 multilayer photographic material including three light-sensitive silver halide emulsion layers on the same side of a single' sup` porteachlcontaining a latent image which comprises, developing the latent image in the sur- K face emulsion layer only,-.printing the developed. image, developing the latent images in the emulsion layers next to the support, transforming the developedv imagesin all of said layers into a silversalt having substantially the same optical properties as the unexposed silver halide in said layers and having substantially no sensitivity to the -light and substantially no reactivity with regard vto thedeveloper used in the further'proc-l essing, selectively exposing the remaining light sensitive silver halide in one of said emulsion layers next to the support, developing and printing the resulting reversal image, transforming the developed image in said last mentioned emulsion layer into a silver salt having substantially the same optical properties as the remaining sil- 'ver salt in the layer and having substantially no sensitivity to the light and substantially no reactivity With regard to the developer used in the further processing,v selectively exposing the remaining light sensitive silver halide in the third emulsion layer, and developing and printing the ,Y resulting reversalimage.

v 8'." 'I he-method of producing photographic images from a multilayerphotographic material including a plurality of light-sensitive silver halide emulsion layers on the same side of a single'support each containing a latent image which comprises, developing the latent image y. in the surface emulsion layer only, printing the 1 developed image, developing the other latent images, transforming all developed silver in all of the layers'into a silver salt-having substangard to the developer used in the further -proc essing, selectively exposing the remaining light sensitive silver halide in one of. the-other emulsion layers, developingand printing the resulting reversal image 'in the last mentioned layer, transforming the developed image( in said last mentioned layer into a.y silver salt having substantially 'the same optical properties as' the` remaining silver salt in the layer and having sut-- stantially no sensitivity to the light and substantially no reactivity with regard to. the developer.

lused in thefurther processing, selectively expostially the same optical properties as the unexposed silver halide in said layers and having substantially no sensitivity to the light and substantiallysno reactivity' with regard to thevdevel-l 9. The method oi'j producing photographic images from a multilayer photographic material including a. plurality o! light-sensitive silver halide emulsion layers on the same side of a single support each containing a latentv image which comprises, developing the latent image in n Jthesurface emulsion layer only, printing the developed image with infrared light, developing the otherlatent images,` transforming all developed `silver in all of the layers into av silver salt having substantially the same ,optical properties as the unexposed silver halide in said layers and having substantially no sensitivity to the light and substantially no reactivity with regard to the developer used in further processing, successively and selectively exposing the remaining light-sensitive silver salt in the emulsion layers other than the surface emulsion layer and developing the exposed layer to form reversal images, said successively produced reversal halide emulsion layers each containing a latent image which comprises, developing the latent images in said emulsion layers, transforming the developed images into a silver salt having substantially the same optical properties as the unexposed silver halide in said layers and having substantially no sensitivity to the light and substantially no reactivity with regard to the developer used in the'- further processing, selectively exposing the remaining light-sensitive silver halide in one of said emulsion layers, developing and printing the Vresulting reversal image, transforming said reversal image into a silver salt having substantially thesame optical properties as the remaining silver salt in said one of'said emulsion layers and having substantially no sensitivity to the light and substantially no reactivity with regard to the developer used in the further processing, selectively exposing the remaining light sensitive silver halide in another emulsion layer, and developing the resulting reversal image in said other emulsion layer.

1l. The method of producing photographic images from a multilayer photographic material including a plurality of light-sensitive silver halide emulsion layers each containing a latent image which comprises, developing the latent.

a'saojsss 5 images in saidlemulsfion layers, transforming the developed images into a silver salt having substantially thesame optical properties as the .unexposed silver halide in said layers and having substantially no sensitivity to the light and substantially no reactivity with regard to the developer used in the further processing. selective.-

ly exposing the remaining light-sensitive silver halide in one of said emulsion layers, developing and printing thel resulting reversal image, .transforming said reversal image into a silver salt having substantially the same optical properties as the remaining silver salt in said one of said emulsion layers and having substantially no sensitivity to the light and substantially no reactivity with regard to the `developer used inthe `further processing, selectively exposing the remaining light-sensitive silver halide in another emulsion layer, and developing the resulting reversalimage in said other emulsion layer and fixing the lm.

12. The :method of producing photographic images from a multilayer photOgraphic material including three light-sensitive silver halide p emulsion layers each 4containing a latent image which comprises, developing the latent images in said emulsion layers, veloped images into a silver salt having substantially the same optical properties 'as the unexposed silver halide in said layers and having substantially no sensitivity to the light and substantially no reactivity with regard to the developer used in the further processing, selectively exposing the remaining light-sensitive silver halide in one of said layers, developing and printy ing the resulting reversal image, transforming the developed reversal image having substantially the same optical properties as the remaining silver salt in said one of said layers and having substantially no sensitivity to the light and substantially no reactivity with regard to the developer used in the further processing, selectively exposing the remaining lightsensitive silver halide in one of the other emulsion layers, developing and printing the resulting reversalimage in the last mentioned layer, transforming the developed image in said last Vmentioned layer into a silver salt having substantially the samey optical properties as the remaining silver salt in the layer and having substantially no ,sensitivity to the light and substantially no reactivity with regard to the def-- veloper used in the further processing, selectively exposing the remaining light-sensitive silver halide in the third emulsion, developing and lixing the film. l

BLA GASPAR.

transforming the de-..

into a silver salt 

